Read Book I and Book II. Through the voice of his teacher Socrates, Plato defines what he considers the ideal forms of justice, leadership, social order, and philosophical discipline throughout The Republic. At the same time, Plato addresses the tension between the pursuit of individual self-perfection and public service.
In Book I, Socrates begins by attempting to define justice by challenging notions held by Cephalus and Polemarchus. Socrates finds their notions wanting, but nonetheless they continue to hold that it is better for a person to be just than unjust. Thrasymachus challenges the assumption that it is good to be just altogether. In Book II, Socrates accepts the challenge from Glaucon and Adeimantus to argue that it is better for a person to be just than unjust and that justice is a good in itself regardless of the consequences associated with it. Socrates begins, however, by looking for justice as a virtue of cities before defining justice as a virtue of persons. He outlines his first version of an ideal city and the producer class of citizens established under the principle of specialization that each person must perform the role for which he is naturally best suited.